Speed-regulating device for sound recording and reproducing machines.



UNITED STATES PTENT OFFICE.

GEORGE OULTON, CHARLES ABLETT, AND WILLIAM EDWARD LIGHTFOOT, OF LIVERPOOL, ENGLAND.

SPEED-REGULATING DEVICE FOR SOUND RECORDING AND REPRODUCING MACHINES.

To all whom it may concern:

Be it known that we, Gnonou OUL'I'ON, CHARLES Annn'r'r, and WILLIAM EowAno Lrerrrr'oo'r, subjects of the King of Great Britain and Ireland, residing at Liverpool,

in the county of Lancaster, England, have invented new and useful Improvements in Speed-Regulating Devices for Sound Itecording and Reproducing Machines, of which the following is a specification.

This invention relates to sound recording and reproducing machines employing disk records and particularly to such machines in which the speed of the motor can be continuously varied so that the relative linear speed between the record line and the stylus remains constant or what is the same thing, the angular speed of the motor increases or decreases according to whether the record commences at the periphery or near to the center of rotation.

The object of this invention is to obtain the differential speed of the motor in a simple and efficient manner and dispense with any connection between the sound box or carrier thereof and the speed controlling device, providing means at the same time for indicating the proper position of the speed controlling device for records of different diameters.

Hitherto, the speed of the motor has been controlled by a cam which was traversed across the brake lever by, the movement of the sound box arm or carrier, the arm being moved as in standard machines by the spiral record line on the record disk acting through the stylus. It has also been proposed to use a sliding cam actuated by the motor through a screw and nut which also traversed the sound box arm or carrier in a direct and positive manner. Accordingto our invention, the sound box arm or carrier is quite free of the speed controlling device and we employ a graduated scale and pointer to indicate the correct starting speed.

looking from underneath; Fig. 3 an, endv elevation of the gear driving the speed Specification of Letters Patent.

Application filed February 24, 1909.

Patented Sept. 19, 1911.

Serial No. 479,202.

changing device, and Fig. 4 an elevation of a cam we use.

Referring now to the drawing, the motor shaft is represented by 1, the base plate of the mechanism is represented by 9, the record carrier or shaft by 3 and the centrif ugal speed changing device or governor by 4. The brake arm 7 is pivoted on a center 9, the usual leather or like shoe 8 being fixed at one end thereof. The boss 10 of the brake arm 7 also has an arm 11 the angle of which in relation to the brake arm 7 may be varied with the position which the governor t occupies in different machines. It might in some cases be dispensed with for instance, the back edge- 12 of the arm 7 might bear against the cam hereinafter referred to if it were found to be convenient to mount the cam behind the said arm. For automatically actuating the brake as the motor is running so as to control the speed of the latter and so that the turntable rotates at a constantly and gradually increasing or decreasing rate, a cam such as 13 Figs. 1, 2 and 4 is fixed on a shaft 11 mounted in bearing'lf), the inner end ot the shaft carrying a worm wheel 16 and the outer end carrying a disk handle 17 marked with a scale 18 opposite to which is fixed on the base plate 2 a pointer 19. The shaft 14 is adapted to slide in the bearings 15 and to carry with it the worm Wheel 16 so as to throw it out of gear with the motor, the cam 13 remaining always in the same position. When the worm wheel is in gear with the motor, it is driven through the shaft 20 by means of a worm 21 fixed on the shaft 3 into which worm a pinion 6 fixed on the shaft 20, gears. At the other end of the shaft 20, is fixed a worm 23 and this gears into the worm wheel 16. The ratios of the several gear wheels through which the cam 13 is driven are so proportioned that as the cam 13 rotates, the eccentric part 24 thereof bearing against the arm 11 of the brake lever at say point 25 may allow the brake shoe 8 to gradually retreat before the friction disk 26 of the governor 41, at a rate which maintains the surface or linear speed of the record disk or the turntable immediately under the stylus practically constant. By sliding the shaft 14,, so as to disengage the Worm wheel 16 with the worm 23, the cam can be set by means of the disk handle 17 so that the arm 11 of the brake lever bears against it at a point which will give any constant angular speed of the turntable that may be desired. In starting the machine with a given size of record disk requiring a constant speed under the stylus, the cam 13 will be so set by hand for the required starting speed, and then the worm wheel 16 will be immediately put into gear with the shaft 20, the result being that the shaft 3 will rotate with a gradually varying angular speed or so that there is a relative constant linear or surface speed between the stylus and the record disk.

It is obvious that the cam may be driven from any other wheel of the motor, the brake lever being modified to suit the position of the axis of the shaft 14.

that we claim as our invention and desire to secure by Letters Patent of the United States, is

l. A speed regulating device for sound recording and reproducing machines comprising in combination, an element having a positive gear driving connection with the motor of said machine and arranged to be disconnected therefrom and adjusted, a cam driven by said element, a governor for the machine provided with a braking member arranged to be positively engaged by said cam, said cam having portionsformed to actuate said braking member for obtaining a constant gradually increasing or decreasing speed of the motor, and means for disconnecting said element from said motor and adjusting the cam relatively to said braking member.

2. A speed regulating device for sound recording and reproducing machines comprising in combination, a shaft having a positive gear connection with the motor of the machine and arranged to be disconnected from the motor, a cam operated by said shaft, and a governor for said machine provided with a braking member arranged to be engaged by said cam, and indicating means operated by said shaft and adapted for manual operation to disconnect said shaft and set the cam With respect to said member.

3. A speed'regulating device for sound recording and reproducing machines comprising in combination, a shaft having a positive gear connection with the motor of the machine and arranged to be disconnected from the motor, a cam operated by said shaft, a governor for the machine provided with a braking member arranged to be engaged by said cam, said cam having portions formed to obtain a gradually decreasing or increasing speed of the motor, and indicat:

ing means operated by the machine for disconnecting the shaft from the vmotor and setting the cam with respect to said braking member and indicating the position of the cam with respect thereto.

4. A speed regulating device for sound recording and reproducing machines comprising in combination, a shaft adapted to be moved into and out of driving connection with the machine, a cam operated by said shaft, a governor for the machine provided with a braking member arranged to be engaged by said cam, and indicating means for setting the cam with respect to said braking member and indicating the position thereof with respect thereto during operation and acting when manually actuated to throw said shaft into and out of driving relation with respect to the machine.

5. A speed regulating device for sound recording and reproducing machines comprisingin combination, a shaft arranged to be thrown into and out of driving relation with the machine, a governor for the machine provided with a braking member, a cam actuated by said shaft and arranged to be held in a position for engagement with said member, and indicating means secured to said shaft to rotate therewith and serving to set the cam with respect to said member and acting when manually actuated to throw said shaft into and out of driving connection with said machine.

6. A speed regulating device for sound recording and reproducing machines comprising in combination, a shaft adapted to be moved into and out of driving connection with the machine, a governor for the machine provided with a braking member, a cam slidably and non-rotatably mounted on said shaft and arranged for engagement with said braking member, said cam having portions formed for engagement with said member to obtain a gradually decreasing or increasing speed of the machine, an indicating disk on said. shaft for moving the same into and out of driving connection with the machine and setting the cam and indicating the position of the cam during operation.

In testimony whereof we have signed our names in the presence of two subscribing witnesses.

GEORGE OULTON. CHARLES ABLETT. WILLIAM EDWARD LIGHTFOOTI Vitnesses:

WILLIAM BINT KENDRIOK, RIDLEY JAMES URQUHA-RT.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

